Electrical windings



p 1958 J. M. N.- HANLET 2,851,765

ELECTRICAL WINDINGS Filed July 26 1955 INVENT OR.

JACQUES MAR/E NOEL HA NLET 774500095 HA FNER ELECTRICAL WINDINGS Jacques Marie N oel Hanlet, Paris, France Application July 26, 1955, Serial No. 524,568

Claims priority, application France July 29, 1954 4 Claims. (Cl. 29155.5)

The present invention relates to improvements in printed electrical windings and methods for making same. The electrical windings concerned herein are for instance electro-magnetic deflection windings, transformer windings, inductance coils and the like.

Printed electrical circuits are known as well as their manufacture. Briefly stated, this manufacture consists of forming conductive patterns upon a dielectric base, for instance by printing with a conducting ink, photoengraving, spraying and the like. In order to prepare with such a method of manufacture an electric component of tridimensional shape, for instance a deflection yoke, it has been proposed to determine the plane development of this winding, apply the said printed conductive development onto a flexible dielectric sheet and, only after this has been done, to shape the component into its tridimensional form. Folding processes have been used, mainly folding into an accordion-like fashion. But, for the present time, it has further been always provided to insulate the printed conductors before any folding whatsoever. Such an insulation may be obtained either by glueing a dielectric sheet on the face of the main base sheet which bears the printed conductor or else by depositing an insulating film thereupon, by painting, evaporating or the like. The flexible dielectric base may consist of paper or plastic material or else, when the conductor is obtained from a metallic sheet, the dielectric may be applied before the printing process proper, provided that it is then translucent.

A two-faced printed circuit may be obtained, when needed, either by a simultaneous development of both circuits to the respective faces of a dielectric sheet, or by a simultaneous printing of these two circuits, side by side, on a face of a dielectric sheet which is afterwards folded along a demarcation line between these circuits. The above-mentioned folding is effected after this first one.

The object of the invention is to omit any need of insulation of a printed pattern when the said pattern must be postwards folded according to an accordionlike fashion as it has been said.

In the drawings, two illustrative embodiments of the invention are disclosed.

Fig. 1 shows a dielectric ribbon bearing a conductive pattern representing a development into a plane of a winding having rectangular turns;

Figs. 2 and 3 are sketches supplementing Fig. 1;

Fig. 4 shows a dielectric ribbon bearing a conductive pattern representing a development into a plane of a winding having turns of the shape shown in Fig. 5;

Fig. 6 shows a dielectric ribbon bearing on both faces thereof a conductive pattern of the kind of the one disclosed in Fig. 3, and

Fig. 7 shows the two interlaced windings obtained after the ribbon of Fig. 6 has been folded.

In all figures the numerical reference 1 is applied to a flexible dielectric ribbon, for instance a ribbon of paper. This ribbon is intended to be finally folded in an ac- 2,851,765 Patented Sept. 16, 1958 cordion-like fashion according to the transverse lines 6.

The development into a plane of a winding having rectangular turns, Fig. 1, is obviously similar to a rectangular waveform, as shown: the upper sides 2 and the lower sides 4 are parallel to the edges of the ribbon. The transverse sides are alternately referred to under the headings 3 and 5.

For the purpose of the invention, further, it is necessary that small lengths of the sides 5 be oblique, as shown at 8.

As near as possible from the sides 3 and 5 of this. pattern, the folding lines 6 are provided.' The pattern. will be obtained, as said, from any known printing proc-- ess. In a preferred method of manufacturing same, however, the pattern will be obtained from evaporating a film of silver through a mask, onto the dielectric surface, and then this film will be thickened by a layer of Zinc, similarly applied for instance.

Once the folding is made, the product will be as shown in (c), Fig. 2, that is to say the winding proper will have this shape. The turns are rectangular ones. The cross-section (a) of this Fig. 2 is taken along the superposed sides 2 of the turns, whereas the cross-section view (1:) of Fig. 2 is taken along the superposed sides 4 of the windings. These cross-section views enable the understanding of the folding. The sides 3, on the one part, and the sides 5, on the other part, will be superposed but with the intercalation of the dielectric sheet 1, the sides 3 and 5 will be present, by pairs, in any plane, as well as the other sides 2 and 4. There Will not be any cross over so that the insulation of the conductive pattern is not necessary.

Of course, before or after the folding, as shown in Fig. 3, a magnetic powder material, specially a ferromagnetic one, may be applied to the one and the other faces of the dielectric base sheet, once provided with the conductive pattern. Such an application may be made from a colloidal iron suspension in water or alcohol. Such a deposit is shown at 7 in Fig. 3 which is a section of the pile taken between two sheets thereof.

In the embodiment of Fig. l, the development of the winding into a plane has been so provided that any turn of the winding is reconstituted from the folding process with two parts only of this development. in the embodiment of Fig. 4, on the other hand, each complete turn of the winding will be obtained from the superposition of four faces of the folded product. It is apparent from Fig. 5 what kind of turns is thereby provided. A pair of windings is actually obtained, the conductor passing from the upper part to the lower part of the composite winding and each part constituting a rhombic turn proper. Such a shape of winding has been described, from another method of manufacturing in a co-pe'nding application of the same applicant. The special effect of such a winding, when used as a deflection winding for a cathode ray tube it to avoid any distortion due to parts of the turns being parallel to the axis of the neck of the said cathode ray tube.

A winding of such a kind is obtained, as apparent, by providing a saw tooth conductive pattern, Fig. 4, more definitely a symmetrical saw-tooth pattern. The apex angles are wide. The folding lines 6 are so chosen that each of the sides of the saw-tooth, 10, is divided into three portions, the parts such as 10 being each half the intermediate part 9.

When such a pattern is folded as indicated, two portions 9 cross over but with the intercalation of one dielectric layer, which bears one of the apex portions of the saw-tooth.

Of course, parts of curves may be substituted at will to the portions of straight lines constituting the shown patterns, without any divergence from the invention proper.

If the saw-tooth has not been provided symmetrical, rhombic shapes of turns of asymmetrical forms will have been obtained. The substitution of portions of curves may enable to obtain circular, ellipsoidal or other forms of turns.

When another printed pattern ,-is provided on the other side of the sheet for instance, with a staggering in the transverse direction of the ribbon from this second pattern with respect to the first, as shown for instance in Fig. 6,- this object being then folded as said, the windings obtained will be of rhombic turns-but one of them will be shifted in height by half a turn with respect to the other. Such a final pattern will be used for embodying deflection windings as described in thesaid application for patent of the applicant, when the deflection must be ensured according to orthogonal planes.

The result of the folding of the ribbon shown in Fig. 6 is such as indicated in Fig. 7. 1

In such a case, the yoke will be formed be enrobing a neck of cathode ray tube with the windings of Fig. 7. In such an application, the individual height of each one of the patterns of Fig. 6 must be provided with a 21rR development; R denotes the radius of the cathode ray tube to which the yoke is intended. A shift by 1r/ 2 is due to be provided in the relative staggering of the two patterns 9-10 and 1112. The width of the ribbon actually is taken equal to 51rR/ 2.

When the pattern on the second face of the ribbon is printed without any shift with respect to the first, two mechanically united but electrically independent windings are obtained, and these windings are quite closely coupled by their mutual inductances. As one of the patterns may be provided with a linear resistance quite different from the other one, a transformer gadget is plainly obtained. Of course, one of the windings may be made of different number of turns than the other one, as it will suflice to print this second winding over part only of the ribbon and the first one over the complete surface of the said ribbon.

Other uses may be provided for the products resulting fromthe putting into practice of the invention.

Having thus described and ascertained my invention, I claim:

1. In the method of manufacturing on a flexible dielectric material a substantially continuous electrical winding, the steps of printing a continuous conductive linear pattern of continuously recurring zig Zag shape extending longitudinally at least along one face of said ribbon, dividing said pattern into a series of consecutive substantially equal sections so separated by folding lines extending across said'ribbon that the conductors of a numberof subsequent pairs of adjacent sections when folded against each other are substantially out of contact, and folding saidpattern bearing ribbon in an accordionlike fashion along the multiplicity of folding lines thereby forming a pile of substantially only serially interconnected windings without any conductor contacting another.

2. Method according toclaim 1 wherein the shape of said pattern resembles that of a rectangular wave form and of transversetconductors of said conductive pattern are arranged close to the folding-lines and wherein the corners of alternating transverse conductors arranged along at least one longitudinal edge. of the ribbon are replaced by an oblique connection breaking said corners.

3. Method according to claim 1 wherein the shape of said pattern resembles that of a saw tooth wave form and the folding lines are arranged to divide such straight line part of said conductive pattern into three portions including a central portion which is twice as large as its lateral portions.

4.. Method accordingto claim 1 wherein each face of i said ribbonis provided with substantially the same pattern and the two patterns, are transversely staggered with respect to each other.

References Cited inthe file of this patent UNITEDSTATES PATENTS 

